A weaker currency means more inflation, but it's a positive for exporters.

However, the Punjab National Bank scam and the kneejerk response of banning Letters of Understanding has raised the cost of capital for exporters.

Critical export-oriented industries like ITES (which is 'Invisibles', not physical exports) and pharma are under pressure due to changes in US regulations.

There will be forex volatility through 2018. The US Federal Reserve is going to raise rates for sure, at least twice.

The European Central Bank and the Bank of Japan are both maintaining Quantitative Easing programmes and negative policy rates. However both central banks have indicated that there will be tightening and "normalisation".

The Bank of England is walking a tightrope, waiting for clarity on Brexit.

If three major hard-currencies tighten money supply, forex rates will swing, though we can't guess at directions.

This will mean higher hard currency debt yields. That could mean a pull-back out of risky Third World assets.

If there are lower forex inflows, that could trigger more rupee weakening.

A vicious circle could start operating if crude prices also trend up at the same time.

India has substantial reserves so there's no fear of a run on the rupee.

Back in 2013-2014 when the currency came under pressure, the RBI took desperate measures, asking banks to organise foreign currency deposits, which it swapped, while bearing the currency risk.